U.S. patent number 3,807,393 [Application Number 05/230,799] was granted by the patent office on 1974-04-30 for surgical retractor.
Invention is credited to Bernard McDonald.
United States Patent |
3,807,393 |
McDonald |
April 30, 1974 |
SURGICAL RETRACTOR
Abstract
This surgical retractor has a pair of opposed slat-like sides
interconnected at their respective ends with divergence at both
ends so that the slats are elastically bowed in arcuate paths with
the concave sides of the slats facing each other. Each of the slats
has cooperating ratchet and pawl arrangements to permit
substantially free lengthwise extension and restricted lengthwise
retraction. In one embodiment, the slats are pivotally
interconnected at their ends with a ratchet arrangement that
permits increase in divergence of the slats and restricts decrease
in divergence. In another embodiment, the slats are elastically
interconnected at their ends. Extension pieces may be used for
varying the size of retractor. An illuminator may be mounted on the
retractor as a transparent flexible sterilizable sleeve for
surrounding a flexible fiber optic bundle thereby providing
illumination from a remote light source. Preferably, the retractor
is formed of plastic for disposal after use.
Inventors: |
McDonald; Bernard (Malibu,
CA) |
Family
ID: |
22866628 |
Appl.
No.: |
05/230,799 |
Filed: |
March 1, 1972 |
Current U.S.
Class: |
600/208; 600/212;
600/245; 600/215 |
Current CPC
Class: |
A61B
1/07 (20130101); A61B 17/0293 (20130101); A61B
1/32 (20130101); A61B 2090/306 (20160201) |
Current International
Class: |
A61B
17/02 (20060101); A61B 1/32 (20060101); A61B
19/00 (20060101); A61b 017/02 () |
Field of
Search: |
;128/3,17,18,20,23,345 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Laudenslager; Lucie H.
Attorney, Agent or Firm: Christie, Parker & Hale
Claims
What is claimed is:
1. A surgical retractor comprising:
a first elongated elastic slat;
a second elongated elastic slat facing the first slat;
means for connecting each end of the first slat to the respective
end of the second slat with mutual divergence of the two slats at
each end so that the slats elastically bow in mutually spaced apart
arcuate paths between their ends with the concave sides of the
slats facing each other; and wherein
each slat comprises a pair of interengaging side pieces slidable
lengthwise relative to each other, each comprising a curved
transverse web, the two webs having their concave sides facing each
other; and
ratchet means for freely extending the length of the first and
second slats and resisting contraction thereof comprising a
plurality of teeth spaced along the length near the center part of
the concave side of one web and pawl means comprising at least one
tooth near the center part of the concave side of the other web for
engaging the ratchet teeth for substantially free lengthwise
extension and restricted lengthwise contraction.
2. A surgical retractor as defined in claim 1 wherein one of the
side pieces comprises a pair of opposed hook-like flanges extending
lengthwise along the side edges on the concave side of the lip and
wherein the web of the other side piece fits between the
flanges.
3. A surgical retractor as defined in claim 1 wherein each of the
side slats includes a pair of spaced apart ribs extending along the
length thereof for forming a channel for receiving tissue adjacent
a surgical incision or the like.
4. A surgical retractor comprising:
a first elongated elastic slat;
a second elongated elastic slat facing the first slat;
ratchet means for freely extending the length of the first and
second slats and resisting contraction thereof;
a pivot for connecting each end of the first slat to the respective
end of the second slat with mutual divergence of the two slats at
each end so that the slats elastically bow in mutually spaced apart
arcuate paths between their ends with the concave sides of the
slats facing each other; and
ratchet means for permitting the slats to pivot away from each
other and restricting pivoting towards each other.
5. A surgical retractor comprising:
a first elongated elastic slat;
a second elongated elastic slat facing the first slat;
ratchet means for freely extending the length of the first and
second slats and resisting contraction thereof;
a pivot connecting each end of the first slat to the respective end
of the second slat with mutual divergence of the two slats at each
end so that the slats elastically bow in mutually spaced apart
arcuate paths between their ends with the concave sides of the
slats facing each other; and
ratchet means for permitting the slats to pivot away from each
other and restricting pivoting towards each other; and wherein each
pivot comprises;
a first hinge half integral with one slat;
a second hinge half integral with the other slat; and
a pin for interconnecting the two hinge halves in pivoting
engagement; and wherein the ratchet means comprises:
an annular array of radially extending ratchet teeth on the face of
one hinge half; and
a tooth engaging pawl on the other hinge half.
6. A surgical retractor comprising:
a first elongated elastically bendable slat;
a second elongated elastically bendable slat facing the first
slat;
pivot means connecting each end of the first slat to the respective
end of the second slat for pivoting the slats between a contracted
position with the faces of the slats in relatively close proximity
and an expanded position with the faces of the slats relatively
spaced apart; and
ratchet means associated with each pivot means for permitting the
slats to pivot away from each other and restricting pivoting
towards each other so that the slats elastically bow in mutually
spaced apart arcuate paths between their ends with the concave
sides of the slats facing each other.
7. A surgical retractor as defined in claim 6 wherein each ratchet
means comprises:
an annular array of ratchet teeth connected to one slat and
extending at least part way around the pivot means;
a pawl connected to the other slat and engaging the ratchet teeth;
and
means for disengaging the pawl from the teeth for permitting the
slats to pivot towards each other.
8. A surgical retractor as defined in claim 6 wherein each of the
elastic side slats is freely extensible in a longitudinal direction
and includes means for limiting contraction in a lengthwise
direction independent of the angle of the pivot.
9. A surgical retractor as defined in claim 8 wherein each of the
elastic side slats comprises:
a female member connected to one pivot means;
a male member connected to the other pivot means and inserted into
the female member, said male member being substantially free to
withdraw from the female member in a longitudinal direction and
being restricted from further insertion in the female member.
10. A surgical retractor as defined in claim 9 wherein the male and
female members each include a bowed transverse web with respective
concave faces thereof facing each other and interengaging ratchet
means on the webs for permitting extension and limiting contraction
and arranged so that further bowing of the webs disengages the
ratchet means.
11. A surgical retractor comprising:
a first arm;
a second arm;
first pivot means for pivotally interconnecting the first and
second arms at one end;
first ratchet means for permitting the arms to pivot away from each
other and restrict pivoting of the arms towards each other;
a third arm connected as an extension of the first arm away from
the first ratchet means;
means for freely extending the combined length of the first and
third arms and resisting contraction of the combined length
thereof;
a fourth arm connected as an extension of the second arm away from
the first ratchet means;
means for freely extending the combined length of the second and
fourth arms and resisting contraction of the combined length
thereof;
second pivot means for pivotally interconnecting the third and
fourth arms at the ends thereof opposite from the first and second
arms respectively; and
second ratchet means for permitting the third and fourth arms to
pivot away from each other and inhibit pivoting of the third and
fourth arms towards each other.
12. A surgical retractor as defined in claim 11 wherein each of the
arms is elastically bendable in a plane transverse to the axes of
the pivot means.
Description
BACKGROUND OF THE INVENTION
Surgical retractors are used for spreading apart or separating the
walls of nartual body orifices or for spreading the margins of
surgical incisions. With the edges of an incision spread apart, the
surgeon has access to the underlying tissues or organs permitting a
clear view of the surgical site and access for a desired surgical
or medical treatment. Thus, for example, an abdominal retractor may
be used in an abdominal incision to hold back the skin,
subcutaneous fat and the internal peritoneal wall for ready access
to the many abdominal organs.
In the past, a variety of surgical retractors have been employed.
Hand retractors are typically steel instruments with a broad
hook-like flap at one end for fitting over the tissue to be
retracted. These are then pulled apart by hand and may be held or
clamped during the surgical procedure. Some surgical retractors
have arms that are interconnected by a gear or rack and pinion
arrangement so that they can be cranked apart and locked in
position. Another surgical retractor has four pivotally connected,
rigid, curved links which can be clamped in any desired position to
hold an incision open. Still another surgical retractor has a rigid
peripheral ring with multiple detachable and movable blades that
can be clamped at any point on the ring to hold a surgical site
open.
Typically, such instruments have been made of stainless steel so as
to be sterilizable between surgical procedures. The instruments are
relatively heavy and stout because, in some cases, substantial
forces may be involved in opening an incision and keeping it open.
Since specially made, the instruments are expensive and it is
costly to repetitively sterilize them and maintain sterility for
surgery. Some of the more complicated retractors need to be taken
apart for cleaning after surgery and reassembled before use.
It is desirable to provide a retractor that is sufficiently
inexpensive that it can be disposed of after a single use thereby
obviating cleaning and sterilization between uses. Such an
instrument should be simple, rugged and versatile.
BRIEF SUMMARY OF THE INVENTION
There is, therefore, provided in practice of this invention
according to a presently preferred embodient a surgical retractor
having a pair of elongated elastic slats interconnected at their
respective ends with divergence at each end so that the slats
elastically bow in arcuate paths therebetween. Ratchet means are
provided for freely extending the length of the slats and resisting
longitudinal contraction thereof.
DRAWINGS
These and other features and advantages of the present invention
will be appreciated as the same becomes better understood by
reference to the following detailed description of a presently
preferred embodiment when considered in connection with the
accompanying drawings wherein:
FIG. 1 illustrates in a general plan view a surgical retractor
constructed according to principles of this invention;
FIG. 2 is a detailed plan view of one end of the retractor of FIG.
1;
FIG. 3 is a side view, partially cut away on line 3--3 of FIG. 2,
of the end of the retractor;
FIG. 4 is a transverse cross section of one extendible side arm of
the retractor of FIG. 1 taken on line 4--4 of FIG. 1;
FIG. 5 is a side view of a female portion of the side arm;
FIG. 6 is a side view of a male portion of the side arm;
FIG. 7 is a fragmentary longitudinal cross section of the female
member taken on line 7--7 of FIG. 5;
FIG. 8 is a plan view of another embodiment of ratchet at and end
connection of a surgical retractor;
FIG. 9 is a plan view of another embodiment of retractor
constructed according to principles of this invention;
FIG. 10 illustrates in side view an extender piece for a surgical
retractor;
FIG. 11 illustrates an illuminator mounted on a surgical retractor;
and
FIG. 12 illustrates the end of the illuminator.
DESCRIPTION
FIG. 1 illustrates in general plan view a surgical retractor
constructed according to principles of this invention. As
illustrated in this drawing many of the details, particularly the
end ratchets, are omitted since shown in substantial detail in
subsequent drawings. Broadly, the retractor of FIG. 1 comprises a
pair of similar, elastically bendable slats 15 pivotally
interconnected at their ends. Each of the side slats 15 has a male
member 16 mated with a female member 17, each of which is described
in greater detail hereinafter. The male and female members are
slidably engaged for length-wise extension and contraction of the
combined side slats 15. Each of the female members 17 is formed as
an extension from a cylindrical hinge half 18 seen in greater
detail in FIGS. 2 and 3. The other hinge half 19 (FIG. 3, hidden in
FIG. 1) is connected to the male member 16. A hinge pin 21 formed
integral with the lower hinge half 19 holds the two hinge halves
together and permits pivotal movement at each end of the surgical
retractor. For ease of assembly of the two hinge halves 18 and 19,
it is convenient to provide a slightly enlarged head 22 on the
hinge pin 21. A pair of intersecting longitudinal slits 23 through
the head 22 and at least a portion of the hinge pin 21 permits the
hinge pin to "collapse" part away as the upper hinge half 18 is
pressed on. When the upper hinge half is pressed on to its full
extent, the hinge pin snaps back out and the head 22 prevents the
two parts from coming apart again. Thus, by simply pressing the two
halves of the hinge together, it can be assembled without any
detachable fasteners.
As seen in greater detail in FIGS. 2 and 3, the pivot at each end
of the surgical retractor is also provided with a ratchet for free
rotation of the pivot to permit the male and female members to
freely increase divergence and restrict decreae in divergence
thereof. Recessed into the upper face of the lower hinge half 19 is
an annular array of radially extending ratchet teeth 24. As will be
apparent, the surgical retractor is typically opened (increasing
divergence of the slats) to only a limited extent during use and
therefore the ratchet teeth 24 need extend only a portion of the
way around the lower hinge half 19.
An aperture 26 extends through the upper hinge half 18 opposite the
row of ratchet teeth 24. A pawl 27 extends through the aperture 26
and engages the ratchet teeth 24. The pawl 27 is an end portion on
a short lever 28 mounted on the upper face of the upper hinge half
by a pair of spaced apart bosses 29. A pin 31 extending between the
bosses supports the lever near its middle. A somewhat enlarged
thumb pad 32 at the opposite end of the lever from the pawl 27
enables one to lift the pawl from engagement with the ratchet teeth
for releasing the ratchet when desired. A coil spring 33 beneath
the thumb pad 32 rests in a recess 34 in the combined upper hinge
half 18 and male member 17. Preferably, a pin 36 on the bottom side
of the lever 28 fits within the spring 33 to assure that it is
always captive and cannot become lost in a surgical site.
Thus, the hinges between the male and female members at each end of
the surgical retractor and the ratchet and pawl arrangement permit
the side slats of the surgical retractor to relatively freely be
increased in divergence since the pawl merely clicks along the
ratchet teeth. One merely pulls on the side slats to open the
retractor. A decrease in divergence of the side slats is restricted
when the pawl engages the ratchet teeth. If it is desired to
release the ratchet, the thumb pad is pressed, disengaging the pawl
from the teeth and the divergence of the side slats can then
decrease.
FIG. 4 is a transverse cross section of one of the side slats 15 in
the portion where the male and female members 16 and 17,
respectively, are engaged. The female member 17 has a curved web 38
forming its principal vertical extent. On its inner or concave
side, that is, the side facing the other side slat 15 (FIG. 1) of
the surgical retractor, the female member has raised lip 39 along
the top and bottom edges. On its outside face, the female member
has a pair of hook-like flanges 41 extending along the length. Very
broadly, the female member thus has a transverse cross section
somewhat like an I-beam.
The male member 16 also has a curved web 43 extending as the
principle portion of its height. The curvature of the two webs 38
and 43 is such that they bow apart from each other. The opposite
edges of the web 43 fit into the re-entrant channel formed by the
hook-shaped flanges 41 on the female member. Thus, the male member
is kept captive in a transverse direction but is free to slide in a
longitudinal direction along the female member. A pair of ribs 44
extend outwardly from the web 43 along the length of the male
member. The ribs 44 are spaced a short distance apart from the
edges of the web 43 so as to clear the tips of the hook-shaped
flanges 41. Thus, the male member has a transverse cross section
somewhat in the shape of a bench or Greek letter pi.
A series of ratchet teeth 46 extend along the length of the inside
of the web 43 on the male member, as best seen in FIG. 5, which is
a side view of the inner face of one end of the male member. Two or
three pawl teeth 47 are provided on the outer face of the web 38 on
the female member as may be seen in FIGS. 6 and 7, which comprise a
view of the outer face of an end of the female member and a
fragmentary longitudinal cross section thereof, respectively.
As best seen in FIG. 4, the pawl teeth 47 engage the ratchet teeth
46 between the webs 38 and 43 of the female and male members. The
teeth of the ratchet and pawl are oriented to permit motion in a
direction tending to extend the length of the side slat 15 formed
of the combined male and female members. The teeth inhibit or
restrict lengthwise contraction of the side slat. The pawl teeth
can ride over the ratchet teeth due to elastic deformation of the
webs 38 and 43 as cammed apart by the teeth.
When it is desired to release the ratchet and pawl arrangement thus
provided, one need only pinch the female member at its side edges
adjacent the flanges 41. Such pinching causes the curved webs to
bend further and be spaced apart a greater distance at their mid
section thereby disengaging the pawl teeth from the ratchet teeth
and permitting the side slats to be contracted in a lengthwise
direction.
In order to use the surgical retractor in, say, an abdominal
incision, the incision is made and the retractor inserted in a
contracted state. Typically, the male and female members are
substantially straight or only slightly curved when made and when
inserted into the incision. The side slats thus are close to each
other when the retractor is inserted. The flesh to be retracted
fits between the two ribs 44 on the male member along part of the
slat length and the flanges 41 on the female member along the rest
of the slat length and is, hence, held substantially captive in the
channels adjacent the webs 43 and 38. Referring to FIG. 3, ribs 48
are provided on the hinge halves substantially as extensions of the
aforementioned ribs and flanges for retaining the flesh to be
retracted at the ends of the retractor.
After positioning the retractor in the incision, the two side slats
are manually spread apart thereby activating the ratchet and pawl
arrangement at the hinges at each end of the retractor. As the
slats diverge adjacent their ends lengthening they are spread
apart, they elastically bend along their length in a plane
transverse to the webs. This elastic bowing of the side slats forms
a double curved opening between the sides of the retractor
approximately as shown in FIG. 1. In addition to increasing
divergence of the side slats, their length may also be increased
merely by pulling the two end portions of the surgical retractor
away from each other. This activates the ratchet and pawl
arrangement between the male and female members and permits
longitudinal extension of the side slats. Such longitudinal
extension may be employed for legthening the available surgical
site or may merely provide the additional length required as the
side slats are bowed apart. It will be noted that as the stresses
due to tissue being retracted increase as the surgical site is
opened, the curvature of the side slats typically increases as well
thereby strengthening the slats against buckling. Since both the
angle at the end of the slats and the length of the slats is
adjustable, the retractor is quite versatile and may be used in
long narrow openings or short wide ones.
When it is desired to close the surgical site, the retractor can be
collapsed quite readily. The length of the side slats is decreased
by pinching the upper and lower edges of the side slats adjacent
the pawl teeth towards each other thereby further bowing the webs
38 and 43 and disengaging the pawl teeth 47 from the ratchet teeth
46. The male member can then slide into the female member freely
for contracting the side slats. The ratchets at the ends of the
retractor are released simply by pressing the thumb pad 32 on the
lever 28 thereby disengaging the pawl 27 from the ratchet teeth 24.
This permits the divergence of the side slats to decrease.
Since the two ends of the surgical retractor are identical, a pair
of identical male members and their integral hinge halves and a
pair of female members with their integral hinge halves are snapped
together to form the surgical retractor. These parts are preferably
made by die casting or rubber mold casting of any of a variety of
modern plastic on synthetic materials which have already come into
wide use in hospitals and other medical practice. Many such
materials are readily sterilizable at the time of manufacture and
assembly and are then individually packaged, not to be opened until
required for surgery. Since such retractors can be made
economically, they can be used once and then discarded, thereby
obviating cleaning and resterilization.
The choice of plastic materials is also advantageous in providing
an appropriate degree of elastic bowing of the side slats when the
retractor is used. The shapes of the male and female members
forming the side slats are such that substantial changes in section
modulus can be made without substantial changes in the overall
dimensions of the side slats. If desired, steel strips can be
imbedded in the plastic for controlled stiffness and strength. With
such possible variations, retractors for symmetrical or
asymmetrical openings of surgical sites can readily be provided,
and substantial changes in size and the stiffness of the surgical
retractor can be made in the course of design for particular
applications.
FIG. 8 illustrates in plan view another embodiment of end ratchet
for an elastic surgical retractor as provided in practice of this
invention. As illustrated in this embodiment, there are no teeth on
the ratchet and continuous adjustment of the width of the surgical
site is provided. A female member 51 of an elastically bendable and
extensible side slat is formed integral with an upper hinge half
52. A male member 53 of the opposing side slat is integral with a
lower hinge half which is hidden beneath the upper hinge half 52 in
FIG. 8. A hinge pin 54 integral with the lower hinge half extends
upwardly through the upper hinge half and ends in a split head 56,
which keeps the two hinge halves together. At least a portion 57 of
the upper hinge half 52 is cylindrical and coaxial with the hinge
pin 54.
A pivot pin 59 also extends upwardly from the lower hinge half and
provides mounting for an eccentric cam 60. A spring 61 between the
side slat 53 and the cam 60 urges the cam in a clockwise direction
as seen in FIG. 8. A release lever 62 extends from the cam for
thumb or finger pressure for turning the cam in a counterclockwise
direction. When the retractor is used, the two side slats 51 and 53
are spread apart manually as hereinabove described, thereby causing
the cylindrical surface 57 on the upper hinge half to ride along on
the eccentric cam 60 and friction therebetween tends to disengage
the cam from the cylindrical surface. When the slats are released,
however, the spring 61 and any friction with the cylindrical
surface 57 urge the cam in a clockwise direction and into wedging
engagement with the cylindrical surface. This wedging action
effectively prevents the side slats from collapsing towards each
other until the release lever 62 is pressed to disengage the
eccentric cam from the cylindrical surface. Continuous motion of
this "toothless" ratchet is thereby provided. If desired small
teeth or minor roughness may be provided on the cam or hinge or
both to inhibit slippage in case the camming surfaces become
lubricated by fluids during surgery.
FIG. 9 illustrates in plan view another embodiment of surgical
retractor constructed according to principles of this invention. As
illustrated in this embodiment, the elastically bendable and freely
extensible side slats are each formed of a pair of extension pieces
66. At each end of the surgical retractor, there is a somewhat
V-shaped end piece 67 so that the retractor has the same general
elongated outline as that hereinabove described and illustrated in
FIG. 1. The elastically bent side pieces are interconnected by the
end pieces 67 which are also elastic but with a somewhat higher
section modulus adjacent the tip of the V to maintain the desired
shape.
Each of the side slat pieces 66 has a male cross section for about
half its length and a female cross section for about half its
length. A side view of one of the side slats 66 is seen in FIG. 10.
One end 71 has a male cross section and the other end 72 has a
female cross section substantially the same as those illustrated in
the transverse cross section of FIG. 4. The male half 71 thus has a
pair of parallel ribs 44' extending along its length. Near the mid
point, these ribs are gradually converted to side flanges 41' on
the female end. A few pawl teeth 47' are provided on the outside
face of the web 38' of the female end. Similarly, a row of ratchet
teeth 46' are provided on the opposite face of the web 43' of the
male end. Thus, when two such side slat pieces are assembled end to
end, the pawl teeth of one engage the ratchet teeth of the
next.
A pair of stop teeth 73 are provided on the web 38 of the female
member and a corresponding pair of stop teeth 74 are provided on
the web 43' of the male member. These teeth 73 and 74 face
oppositely to the ratchet and pawl teeth. This permits the male end
of one extension piece to be inserted into the female end of
another extension piece, however, it limits the extent of
withdrawal of the two parts so that over-extension of the side
slats is avoided. This is typically of no problem in an embodiment
as illustrated in FIG. 1 where the entire extension of the side
slats occurs in a single ratchet and pawl assembly. In an
embodiment as illustrated in FIG. 9, however, a portion of the
extension may occur in each of three ratchet and pawl combinations.
It could occur that one of these combinations could be overextended
inadvertently and the stop teeth are employed to prevent this from
happening.
It will be apparent that an extension piece 66 may be employed in
each side slat of a retractor as hereinabove described and
illustrated in FIG. 1 in order to obtain a greater length. This can
be provided simply by separating each of the illustrated side slats
15 and inserting an extension piece having half male and half
female cross sections between the separated ends.
FIGS. 11 and 12 illustrate a means for illuminating a surgical site
in combination with a retractor as provided in practice of this
invention. It will be apparent, however, that the surgical
illumination so provided can be employed with other surgical
retractors or similar arrangements adjacent a surgical site. As
illustrated in this embodiment, the female portion 17 of a side
slat has the illuminator mounted thereon. A plastic clip 76 is
snapped onto the flange 41 and lip 39 at the top edge of the
retractor. The clip is sufficiently elastically flexible that its
lower hook-like legs 77 at each side can spring over the flange and
lip for easy installation and tight gripping. A hollow spherical
socket on the top portion of the clip accommodates a ball 78 which
readily snaps into the socket to permit free rotation and tilting
through a substantial angle. If desired, the ball may be partially
split or the clip adjacent the socket may be partially split to
assist in insertion of the ball into the spherical cavity. The ball
is preferably slightly larger than the cavity so as to be tightly
gripped. The friction between the socket and the ball holds the
assembly in any position in which it is placed.
A pair of cooperating fingers 79 on the top of the ball define a
cylindrical space therebetween into which a fiber optic bundle 81
is snapped. A thin, flexible transparent plastic sheath 82
surrounds the fiber optic bundle so that only the clip and sheath
need be sterilized in order to bring the fiber optic bundle into
the surgical site, that is, the fiber optic bundle itself need not
be sterilized since it is isolated from the site by the
sterilizable sheath. The end of the fiber optic bundle is adjacent
a conventional light source 83 which can be a great distance from
the surgical site.
The other end of the fiber optic bundle which is illustrated in
FIG. 12 terminates at the transparent end 84 of the plastic sheath.
In this way, the fiber optic bundle is adjustably fixed to a
surgical retractor which is typically mounted in the surgical site.
The fiber optic light source is fixed in position but, because of
the flexibility of the end of the bundle, it can be manipulated and
directed to any desired location within the surgical site for
either illumination or observation or, if desired, the bundle may
be used for transmission of an intense light beam for pinpoint
cauterization. Illumination or observation occurs through the
transparent end 84 of the sterilizable plastic sheath 82.
The fiber optic bundle 81 is a conventional item made up of a large
plurality of glass or plastic fibers having carefully controlled
variations in index of refraction. Because of this, light entering
one end of a fiber within the bundle is repetitively reflected
along the length of the bundle despite curving thereof and is
projected from the other end of the bundle. Since a large number of
fibers are used in a bundle, excellent flexibility can be obtained.
Illumination of a surgical site by a fiber optic bundle from a
remote light source is quite advantageous in modern surgery. Most
light sources generate a large amount of heat and by transmitting
the light through a fiber optic bundle to the surgical site, the
heat can be dissipated at the remote light source without any
danger of burning the patient. The removal of the electrical hazard
from the proximity of the patient or surgical personnel is also of
significant importance, not only in eliminating shock hazard but
also in avoiding explosion hazards with some anaesthetics.
Although limited embodiments, of surgical retractor constructed
according to principles of this invention have been described an
illustrsted herein, many modifications and variations will be
apparent to one skilled in the art. Clearly, many ratchet and pawl
arrangements can be adapted to a retractor having elastically
bendable and extensible side slats. A variety of modifications in
other aspects of the detailed structure will be apparent to one
skilled in the art. It is therefore to be understood that within
the scope of the appended claims, the invention may be practiced
otherwise that as specifically described.
* * * * *